1. Field of the Invention
The present invention relates, in general, to segmented pre-cast concrete piling systems used for underpinning existing buildings.
2. Information Disclosure Statement
Pre-cast concrete piles have been in use for the purpose of supporting and/or leveling structures for a number of years. These piles are vertically stacked one upon another and driven into the soil to a point of refusal at which a load bearing capacity may be obtained. These segmented piles, installed properly, provide greater support than a shallow method of underpinning, however, there are problems with the existing art.
In unstable soils, there is great potential for upward, downward, and lateral movement. These factors affect the integrity of the pile, as existing segmented piles have no, or very little, lateral support to prevent separation of the pile segments thus causing misalignment, separation of the pile, and loss of support.
Another important factor with segmented piling systems is proper alignment during installation. With no, or very little, lateral support between segmented piles using existing procedures, it is difficult to insure proper alignment and prevention of lateral movement during, and after, installation.
Knight, U.S. Pat. No. 5,288,175, issued Feb. 22, 1994, discloses a continuously reinforced segmental precast concrete underpinning pile system including a plurality of precast concrete piles and a high strength wire strand joining each of the piles.
Willcox, U.S. Pat. No. 5,505,561, issued Apr. 9, 1996, discloses a self-piloting compressible piling system including a plurality of pre-formed pile sections having bores therethrough and adapted to be arranged in end-to-end relation such that the bores are concentrically collinear, an auger plate positioned beneath the lowest of the pile sections, and a tension-bearing cable attached to the auger plate and extending through the bores of the pile sections to load the pile sections and auger plate in compression.
Nothing in the known prior art, either singly or in combination, discloses or suggests the present invention.
The present invention is intended for the purpose of repair and prevention of settlement of structures located on unstable soil. The present invention provides proper alignment of segmented piling system during installation, verification of depth during installation, prevention of lateral movement of the piling system during installation and throughout the life of the piling system. The increase in bending strength and lateral support in the piling system results in improved long term structural support for the building being supported.
A key concept of the present invention is to provide a system including a unique combination of a starter pile segment, a plurality of follower pile segments, and a plurality of connecting rods which allows the pile segments to be driven into the soil one pile segment at a time with each pile segment aligned, collinear and concentric with one another.
The present invention relates to a segmented pre-cast concrete piling system used for underpinning existing buildings. The piling system of the present invention provides a continuous connection of components for vertical and horizontal control of the piling itself during installation and throughout the life of the piling. The significant improvement of the present invention over the prior art is the increased lateral support and bending strength of the piling system provided by installation of steel connecting rods interconnecting segmented concrete pilings. The significant increase in bending strength of the piling system provides for improved vertical support of an existing structure.
It is an object of the present invention to provide a segmented piling system for underpinning existing buildings, including a plurality of segmented piles with each pile interconnected by connecting rods.